Magenta couplers

ABSTRACT

Magenta couplers of the 5-pyrazolone type which have a phenylcarbamylamino substituent in the 3-position of the pyrazolone nucleus and which have, as a substituent in the 1position of the pyrazolone nucleus, a 2&#39;&#39;,4&#39;&#39;-dihalo-6&#39;&#39;alkoxyphenyl group or a 2&#39;&#39;,6&#39;&#39;-dihalo-4&#39;&#39;-alkoxyphenyl group.

United States Patent Gandino et al.

MAGENTA COUPLERS' Inventors: Mario Gandino; Beretta Paolo, both ofSavona, Italy Assignee: Minnesota Mining and Manufacturing Company, St.Paul, Minn.

Filed: July 3, 1972 Appl. No.: 268,449

Related US. Application Data Continuation of Ser. No. 43,03l, June 3,1970, abandoned.

Foreign Application Priority Data June l3, 1969 Italy 37892/69 US. Cl.96/100 Int. Cl G03c 1/40 Field of Search 96/100 Primary Examiner-RonaldH. Smith Assistant Examiner-Richard L. Schilling Attorney, Agent, orFirm-Alexander, Sell, Steldt & DeLal-lunt [57] ABSTRACT Magenta couplersof the S-pyrazolone type which have a phenylcarbamylamino substituent inthe 3- position of the pyrazolone nucleus and which have, as asubstituent in the' l-position of the pyrazolone nucleus, a2,4'-dihalo-6'-alkoxyphenyl group or a 2',6-dihalo-4-alkoxyphenyl group.

8 Claims, 4 Drawing Figures MAGENTA COUPLERS This is a continuation ofapplication Ser. No. 43,031, filed June 3, 1970, now abandoned.

The present invention relates to photographic couplers and morespecifically to couplers which react with an oxidation product ofdevelopers of the paraphenylene diamine type to provide magenta dyes.

The formation of colored photographic images by the reaction betweenphotographic color couplers and oxidation products of developers of theparaphenylene diamine type, is well known in silver halide colorphotographic technology. In the subtractive color process, such imagesare colored, respectively, yellow, magenta and cyan, which colors arecomplementary of the three primary colors blue, green and red. Goodcolor reproduction requires the three images to appear as a balancedwhole. To achieve such a color balance," couplers must often be employedwhich provide magenta dyes having absorption maxima which are shiftedsometimes towards higher and sometimes towards lower wavelengths andwhich exhibit absorption curves which contain little if any undesiredsecondary absorption. Magenta dyes have been produced from couplers ofthe l-phenyl-3-acylamino-5-pyrazolone type, as 25 shown by US. Pat. Nos.2,348,463; 2,369,489; 2,511,231; 2,600,788; 3,062,653; and British Pat.No.. 904,852. Certain of these patents describe efforts to vary couplerproperties by varying substituent groups of the couplers.

Good color reproduction also requires dyes which yield good imagecontrast and high image color density. In addition, it is essential forpreservation of the colored images that the dyes which are derived fromcouplers have good stability characteristics. Briefly, the presentinvention provides a S-pyrazolone coupler having a 5pyrazolone nucleuswhich contains in the 3- position thereof a phenylcarbamylamino groupand which contains in the l-position thereof a2',4'-dihalokXyPh!lZl....9 o a 2.....-5. 2 9:i..-,. alkoxyphenyl group.

The preferred couplers of the present invention may be represented bythe general formula wherein two of the A groups are halogen, theremaining A group is alkoxy, and wherein R is alkyl, alkoxy, or

wherein R is alkyl or alkoxy.

The alkoxy group representing one of the A groups may have from 1-18carbon atoms, but preferably is a lower alkoxy group. The alkoxy oralkyl group represented by R or R preferably has at least five carbonatoms (so as to provide ballasting characteristics) and may have as manyas about 20 carbon atoms.

The present invention also provides silver halide emulsions containingat least one of the aboveidentified couplers.

The couplers of the present invention and the magenta dyes derivedtherefrom exhibit improved stability characteristics in comparison tocouplers and magenta dyes of the prior art. The magenta dyes prepared byreacting couplers of the invention with any of a number of paraphenylenediamine-type developers exhibit unusually satisfactory light-absorptioncharacteristics. These highly desirable characteristics of the 5-pyrazolone couplers of the present invention are dependent upon the factthat the pyrazolone nucleus bears in the 1-position a2',6'-dihalo-4-alkoxyphenyl or a 2',4-dihalo-6-alkoxyphenyl substituent,and bears in the 3-position a phenylcarbamylamino substituent.

The particular absorption properties of the magenta dyes prepared fromcouplers of the invention depend primarily upon the nature of thesubstituent in the 3- position of the pyrazolone nucleus. If thissubstituent is a phenylcarbamylamino group having substituted on thephenyl group thereof an alkyl group or an alkoxy group (which groupsimpart to the molecule nonbleeding characteristics), the resulting dyeshave absorption maxima shifted towards lower wavelengths. lf thissubstituent is a phenylcarbamylamino group having substituted on thephenyl group thereof a substituent of the sulfoanilide type substitutedwith .an alkyl or an alkoxy (which groups also impart non-bleedingcharacteristics to the molecule), the resulting dyes have absorptionmaxima shifted towards higher wavelengths.

Silver halide photographic emulsions containing couplers of the presentinvention may readily be prepared by known techniques, such as thesolvent dispersion technique described in US. Pat. Nos. 2,322,027;2,801,170; 2,801,171 and others. in addition to hydrophilic colloidalbinders such as gelatin, etc., the emulsions may contain such commonphotographic adjuvants as chemical sensitizers, optical sensitizers,stabilizers, plasticizers, antioxidants, u.v. absorbers, and the like.Silver halide (chloride, bromide, iodide or mixtures thereof) emulsionsmay have the couplers of the invention added thereto either before orafter optical sensitization thereof. The emulsions may be spread onknown photographic bases (e.g., polyester film, glass, paper, etc.) toform photographic elements.

The emulsions can be developed with primary aromatic amine developers,e.g., of the paraphenylene diamine type. Developers of this type areexemplified as follows:

Developer 1 Part A H O wdroxylamine hydrochloride 1.N-diethylparaphenylene diamine sulfate Part B Sodium tripolyphosphute 2Anhydrous sodium carbonate 65 Anhydrous sodium sulfitc 2 Potassiumbromide 1 Sodium hydroxide 2 Solution A is poured into solution B toyield the devel- I oper bath. l-(2'-methoxy-4,6 dichloro)-phenyl-3-p-Developer 2 dodecylphenyl-ureido-S-pyrazolone Coupler 4 Sodiumhexametaphosphate 5 Anhydrous sodium sulfite 4 g2-amino-5-diethyluminotoluene CH;FNHC 0 NII- hydrochloride 3 g Sodiumcarbonate. monohydrate g 00mm Potassium bromide 2 g N Water to make l000ml. 10

Cl OCH;

Developer 3 2-amino-S-N.N-ethyLfi-methancsulfonamidol 5 Cl ethyl-toluenesulfonate Anhydrous sodium sulfite Sodium hydroxide Sodium metaborate lSodium sulfate -0 b man ho:

can

The following examples are illustrative of couplers of O: 1 CH;-C--NHCONHC "H25 5 LL I or 00H;

v c1 c1 1 CH3 3 l-(2-methoxy:4,6-dichloro):phenyl-3-(4-sulfo-p- 5dodecyl-amhdo)-phenyl-ureldo-5-pyrazolone Couplers of the prior art withwhich the couplers of thel-(2',6'-dichloro-4'-meth0xy)-phenyl-3-p-dodecylinvention y be comparedinclude:

phenylureido-S-pyrazolone Coupler 6 Coupler 2 40 I CH;CNHCOCHO CHg-CNHCONHSO2NHC12H25 0:!) ii 32115 5 1| tsHal 0: N N

i C! -OOHa Coupler 7 l-( 2 ',6-dichloro-4 -methoxy )-phenyl-3-[ 4'-sulfo-pdodecylanilidol-phenyl-ureido-S-pyrazolone 5 5 Coupler 3CHz--CNHCOOH-O CH CNHCONH 0 E 0:23 IJI Q 12 25 I O= 1m (IJZHS Q o1 OCH:

Coupler 8 The above couplers 6, 7 and 8 are of the type described inEnglish Pat. No. 904,852. Couplers 9 and 10 are of the type described inUS. Pat. No. 2,600,788.

EXAMPLE 1 (COUPLER 1) A. 2,6-dichloro-4-methoxy-aniline A saturatedsolution of gaseous HCl in methanol was prepared by bubbling dry gaseousHCl in 2.4 liters of anhydrous methanol with ice-bath cooling. Aftersaturation was complete, 290 g. of p-nitroso phenol (m.p. l33l 36 C,purified by the procedure reported in Journal of Organic Chemistry, 32,1967, p. 156) were added with continuous stirring and bubbling ofgaseous HCl through the reaction mass, the temperature of the mass beingmaintained in the range of l20 C. After stirring for an additional halfan hour with bubbling gaseous HCl, the material was filtered, washedwith ether and dried. The product was dissolved in 1.5 liters ofmethanol and 120 ml of water; the solution was refluxed, decolorizingcharcoal was added and the filtrate was poured, with stirring, intoliters of cold water. The solid was filtered out and the product wascrystallized from 800 ml of toluenated methanol to yield 203 g. of2,6-dichloro-4-methoxy-aniline in the form of fine small white needlesmelting at 72-74 C. B. 2,6-dichloro-4-methoxy-phenyl-hydrazine A mixtureof g. of 2,6-dichloro-4-methoxyaniline, 420 ml of concentrate HCl, and210 ml of distilled water were vigorously stirred for 1 hour at roomtemperature. The mass was then cooled to between +2 C and -2 C, and asolution of 55 g. of sodium nitrite in m1 of demineralized water wasadded dropwise thereto. At the end of the reaction, the mass was stirredfor an additional half an hour and the excess of nitrous acid presentwas destroyed with urea. The resulting solution was rapidly filtered andslowly poured into a solution of 700 g. of SnC1 '2l-l O, 3.5 l. ofconcentrated HCl and 1.7 l. of demineralized water, maintained at 0 Cwith stirring. After continued stirring for an additional 4 hours, themass was permitted to stand undisturbed overnight in a refrigerator. Thesolid formed was filtered off, washed thoroughly with cold water, andwas suspended in 3.0 liters of demineralized water. The mass was cooledto 10 C and made basic under stirring with a 30% NaOH solution, takingcare that the temperature did not exceed 12 C. The solid was filteredand extracted with ether, and the extract dried overnight over sodiumsulfate. The ether was evaporated to dryness and the residue wascrystallized from heptane. 77 g. of the hydrazine having a m.p. of124-l25 C were obtained. (Analysis; N% Calculated: 13.59; Found 13.53).

C. l-(2',6'-dichloro-4-methoxy)-phenyl-3-amino-5- pyrazolone Theso-prepared hydrazine was condensed with,B-ethoxy-B-imino-ethyl-propionate to give the 3-aminopyrazolones by themethod of US. Pat. No. 2,600,788. The product, crystallized bytoluenated methanol, melted at 23l-232 C.

N% Calculated: Cl% Calculated:

Found 15.20

Analysis:

Fo und 25.5 3

D. Coupler To 720 ml of pure nitrobenzene were added 232 g. of anhydrousaluminum trichloride in small portions. During this addition thetemperature rose to 45 C. Then 240 g. ofl-(2',6'-dichloro-4'-methoxy)-phenyl- 3-amino-5-pyrazolone were added insmall portions, the temperature rising to 55 C. Thereafter, 252 g. ofp-dodecyl-phenyl isocyanate (obtained by phosgenation in toluene ofp-dodecyl-aniline) were added drop-- Analysis: C% Calculated: 62.00;Found: 62.20

H% Calculated: 6.89; Found: 6.99

N% Calculated: 9.98; Found: 9.99

EXAMPLE ll (COUPLER 2) To 112 ml of a 59 percent by weight solution of4- sulfo-p-dodecylanilido-phenyl-isocyanate in toluene at 95 C wereadded 40 g. of the 3-amino pyrazolone of Example l. The resultingsolution was refluxed at 110 C for 2 hours. A 250 ml portion oftoluenated methanol was added with great care, when the distillationstabilized an additional 500 ml of methanol were added dropwise and thedistillation was continued until 750 ml of distillate had been removed.The material was cooled, poured into a mixture of 3 l. of ice water and200 ml of concentrated HCl, stirred, filtered, thoroughly washed withwater, and dried at 50 C to yield a product melting at ll30 C. Theproduct was boiled in petroleum ether, dissolved in benzene andprecipitated with ligroin. After filtration the product was trituratedin ligroin-petroleum ether l:l filtered, and dried at 50 C. A white,fine powder melting at ll38 C was obtained.

Found: 9.5 Found: 4.2

N% Calculated: 9.7; 8% Calculated: 4.4;

Analysis:

The hydrochloride of 4,6-dichloro-2-methoxy-aniline was prepared bychlorination in dioxane of orthoanisidine hydrochloride with sulfonylchloride at a temperature of from room temperature to C for a period of2-3 hours. The raw product was purified by dissolution in hot methanol,the solution poured in water separated out the4,6-dichloro-2-methoxy-aniline separating out as a dark oil upon pouringof the solution into water. The oil was extracted with ether and fromthe extracts (dried on sodium sulfate) the hydrochloride wasprecipitated out with anhydrous, gaseous hydrochloric acid. The aminewhich was obtained was diazotized and reduced as described in thepreceding preparation to give the corresponding phenylhydrazine whichwas converted to pyrazolone as described in paragraph C of Example Iabove. The l-(2'-methoxy-4',6'-dichloro)- phenyl-3-aminopyrazolone whichwas obtained melted at 198-l99 C.

Analysis: N% Calculated: 15.32; Found: 15.45 Cl% Calculated 25.90;Found: 25.90

The so-prepared product was reacted with p-dodecyl-phenyl-isocyanateusing the procedure of Example I to provide a fine white powder meltingat l72-l 74 C.

Analysis: CZ Calculated: 62.00; Found: 6|.84 H} Calculated: 6.82: Found:6.77 N% Calculated: 9.98; Found: 9.96

EXAMPLE lV (COUPLER 4) nitrile and ethanol yielded the coupler, mp. 152l 5 5 C.

Analysis: C% Calculated: 62.50; Found: 62.70 H% Calculated: 7.26: Found:7.49 N% Calculated: 8.80; Found: 8.70

EXAMPLE V (COUPLER 5) Example II was repeated utilizing the 3-aminopyrazolone of Example Ill. A white powder melting at l28l32 C wasobtained.

EXAMPLE Vl 2 grams of each of couplers l to 10 were individuallydissolved in a solution of 6 ml of butyl phthalate and 12 ml of ethylacetate, and each solution was then emulsified with 40 ml of a 4 percentgelatine solution. The resulting emulsions were then diluted with waterto l00 ml and a fraction of each emulsion thereof, containing 2 mM ofcoupler, was mixed with 200 ml of a nonoptically sensitized, 7 percentgelatin-silver bromidechloride emulsion. The resulting emulsions wereeach spread on a cellulose acetate base, dried, exposed in a wedgeexposimeter, developed with the abovementioned developers 1 and 2,bleached and fixed.

In Table l the absorption maxima of the dyes obtained, expressed in ma,are shown.

FIGS. 1, 2, 3 and 4 of the drawings are dye absorption curves whereinLog D (Density) is plotted against wavelength.

FIGS. 1 and 2 compare the absorption curves of dyes prepared fromcouplers 5, 6 and 10 and 3, 6 and l0 respectively, each of the dyesbeing derived from the previously described developer 1. These curvesindicate that the dyes resulting from couplers of the invention tend toavoid the unwanted absorption in that area of the spectrum (denoted bythe arrows) which is characteristic of the prior art dyes.

FIGS. 3 and 4 compare the absorption characteristics of dyes preparedfrom couplers 3, 6 and 10 and 5, 6 and 10 respectively, each dye beingderived from the previously described developer 2. These curves indicatethat the absorption of the dyes derived from couplers of the inventionmay conveniently be shifted toward longer or shorter wavelengths to meetthe color balance requirements of the materials in which they may beincorporated.

EXAMPLE VII 6 grams of each of couplers l, 3, 8 and 9 were dissolved ina mixture of 1.8 ml of dibutyl phthalate, 1.8 ml of tricresyl phosphate,and l6 ml of ethyl acetate.

Each solution was then emulsified with 60 ml of a 4 What we claim is:

percent gelatin solution and diluted to l ml with wal. A silver halidephotographic emulsion which inter. A portion of each dispersion(containing an antioxcludes a coupler of the formula idizing agent and aU.V. absorber) was added to a nonoptically sensitized silverchloride-bromide emulsion to provide a coupler concentration of 35 mMper Kg of & {1

emulsion. M \N/ R Each emulsion was spread on a paper base, dried,exposed in a shaded wedge" exposimeter, developed A A wlth theafore-mentloned developer 3, bleached and fixed. The sensitometric dataof Table 2 were derived from fresh images and from images subjected tostorage under the indicated conditions.

T A B L E 2 Non-stored image Stored image Exposure in fadometer Stored24 hours (xenon lamp) at 90C and Coupler Do D ADoB Sr 'y B G D max h h20 h 40 h A D Sr relative sensitivity expressed in log It required toprovide a density of L0;

contrast;

minimum density (fog) measured under bluelight (B) and green light (G)maximum density maximum density differential fog differential measuredunder blue light (indicating stability of residual coupler) ll ll ll llII ll In comparison to the prior art couplers, the couplers wherein twoof the A groups are halogen, the remaining of the invention are thusshown to impart to the emul- A group is alkoxy, and wherein R is alkyl,alkoxy, or sion greater sensitivity, contrast and maximum density.

Moreover, the couplers of the invention and the dyes 35 R preparedtherefrom exhibit greater stability than do the compared prior artcouplers and dyes.

EXAMPLE wherein R is alkyl or alkoxy. 6 grams of each of couplers l, 8and 9 were dissolved 4o 2. The emulsion of claim 1 wherein the A groupin amixture of 3.6 ml of dibutyl phthalate, 3.6 ml of triwhich is alkoxycontains l-l8 carbon atoms, and cresyl phosphate and l6 ml of ethylacetate. Each soluwherein the alkoxy or alkyl group represented by R ortion was emulsified with 60 ml of a 4 percent gelatin so- R contains5-20 carbon atoms,

lution and diluted to 100 ml with water, and a portion 3. A silverhalide photographic element which inof each of the resulting dispersionswas added to a silcludes a layer of the emulsion of claim 1.

ver chloride-bromide emulsion (sensitized to green 4. A silver .halidephotographic emulsion which inlight by addition of an opticalsensitizer) to provide a cludes a coupler of the formula concentrationof coupler equal to 35 mM per Kg of emulsion. Each emulsion was spreadon a paper base H: l NHOONHCuHn 'and dried. Some specimens were storedfor 7 days at o= 38 C and 70 percent R. H. and others were stored forthis period at 22- -2C and 40-45 percent R.H. Each specimen was thendeveloped with the above-described 01 c1 developer 3, bleached andfixed, and the differences, between the two sets of specimens wereevaluated. The

pertment data are set out 1r1 Table3. 7 my 6 5. A silver halidephotographic emulsion which in- T A B L E 3 cludes a coupler of theformula l 0.04 0.0 O: 8 0.18 27.2 9 0.26 23.7 N

. ASr change in relative sensmvlty 1 1 A7 '70 change in contrast.percent.

This data is indicative of the unusual stability of couplers of thepresent invention. W W oo in Q 12 6. A silver halide photographicemulsion which includes a coupler of the formula T Q CmHz:

01 OCH:

7. A silver halide photographic emulsion which in- I cludes a coupler ofthe formula

1. A SILVER HALIDE PHOTOGRAPHIC EMULSION WHICH INCLUDES A COUPLER OF THEFORMULA
 2. The emulsion of claim 1 wherein the A group which is alkoxycontains 1-18 carbon atoms, and wherein the alkoxy or alkyl grouprepresented by R or R'' contains 5-20 carbon atoms.
 3. A silver halidephotographic element which includes a layer of the emulsion of claim 1.4. A silver halide photographic emulsion which includes a coupler of theformula
 5. A silver halide photographic emulsion which includes acoupler of the formula
 6. A Silver halide photographic emulsion whichincludes a coupler of the formula
 7. A silver halide photographicemulsion which includes a coupler of the formula
 8. A silver halidephotographic emulsion which includes a coupler of the formula